cmd/dist: fix bootstrap failure when GOHOSTARCH is set

Fixes #33977

Change-Id: I4b136788f08b08c53087af8d3cd56125e620b51b
Reviewed-on: https://go-review.googlesource.com/c/go/+/197602


Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

src/cmd/dist/buildtool.go

@@ -250,6 +250,9 @@ func isUnneededSSARewriteFile(srcFile string) (archCaps string, unneeded bool) {
 	archCaps = fileArch
 	fileArch = strings.ToLower(fileArch)
 	fileArch = strings.TrimSuffix(fileArch, "splitload")
+	if fileArch == os.Getenv("GOHOSTARCH") {
+		return "", false
+	}
 	if fileArch == strings.TrimSuffix(runtime.GOARCH, "le") {
 		return "", false
 	}